Treatment of immune-mediated temporal lobe epilepsy with GAD antibodies

Seizure. 2015 Aug:30:57-63. doi: 10.1016/j.seizure.2015.05.017. Epub 2015 Jun 6.

Abstract

Purpose: Temporal lobe epilepsy with antibodies (abs) against the glutamic acid decarboxylase 65 isoform (GAD-TLE) is known as an immune-mediated neurological syndrome. Here we evaluate the therapy response to various immunotherapies and epilepsy surgery in this syndrome.

Method: All patients with GAD-TLE and follow-up data and stored serum and CSF samples, identified and treated at the Bonn centre from 2002 to 2010, were studied retrospectively. Seizure freedom for ≥1 year and reduction of ≥50%, i.e. therapy response, were assessed. GAD-ab titres and neuropsychological performances were documented prior and after individual interventions.

Results: Thirteen patients with GAD-TLE were identified with the following seizure responses: corticosteroids (5 responders out of 11 treated patients); i.v. immunoglobulins (1/5), apheresis therapy (1/8); and natalizumab (1/1), selective amygdala-hippocampectomy (2/3). None of the patients achieved sustained seizure freedom apart from one patient. This patient was on antiepileptic drug treatment after discontinuation of immunotherapy.

Conclusion: The seizure response to immunotherapies in patients with GAD-TLE was poor. Corticosteroids were the most effective regarding seizure response. Especially the poor effects of apheresis therapies support the idea that GAD-abs are not directly pathogenic. None of three patients was seizure-free after temporal lobe surgery suggesting that GAD-TLE patients respond worse than others to this type of intervention. Our results reflect the chronic course of the disease with low likelihood for patients with GAD-TLE to attain long-term seizure freedom.

Keywords: Autoimmune epilepsy; GAD-abs; Temporal lobe epilepsy.

MeSH terms

  • Adolescent
  • Adult
  • Anticonvulsants / therapeutic use
  • Autoantibodies / blood*
  • Autoimmune Diseases of the Nervous System / blood
  • Autoimmune Diseases of the Nervous System / cerebrospinal fluid
  • Autoimmune Diseases of the Nervous System / therapy*
  • Child
  • Epilepsy, Temporal Lobe / blood
  • Epilepsy, Temporal Lobe / cerebrospinal fluid
  • Epilepsy, Temporal Lobe / immunology*
  • Epilepsy, Temporal Lobe / therapy*
  • Female
  • Follow-Up Studies
  • Glutamate Decarboxylase / immunology*
  • Humans
  • Immunotherapy
  • Male
  • Methylprednisolone / administration & dosage
  • Middle Aged
  • Neuropsychological Tests
  • Neurosurgical Procedures
  • Retrospective Studies
  • Treatment Outcome
  • Young Adult

Substances

  • Anticonvulsants
  • Autoantibodies
  • Glutamate Decarboxylase
  • glutamate decarboxylase 2
  • Methylprednisolone